High Explosives

Abstract

MR. LLOYD GEORGE'S recent speech in the House of Commons, as Minister of Munitions, emphasised the very important part played by high explosives in the present war. It is essential at the outset to distinguish clearly between a propellent charge, which forces the projectile or shell through the bore of the gun, and the high explosive charge filling the shell itself and causing it to burst, through the inter. vention of a time or percussion fuse. Modern military propellants consist of gelatinised gun-cotton(nitro-cellulose), either alone or mixed with varying proportions of nitro-glycerine, pressed into any required shape. The finished explosive is of a colloidal, horny nature, and a piece of it held in the fingers, whilst burning, can be blown out quite easily. A charge lit in the enclosed space of the chamber eft a gun can discharge a projectile with a velocity of about 1000 yards per second, developing in the chamber a pressure of, perhaps, twenty tons on the square inch. If the same quantity of the ungelatinised material were ignited in the gun-chamber it would detonate and blow the gun to pieces.